Jupiter may be the leader of the Mortal Gods but Juno is very much its public face.
The philanthropist Eliza Finch is the CEO of The Olympus Foundation, a charitable organization whose main goal is to make the world a better place. She was given this position by Jupiter himself, who claims that the two of them have been in love for eons. As Jupiter is one of only two member of the Mortal Gods who remembers their supposed past lives, she can’t really say if this is true or not. All she can say is that in this life, she is very much a lesbian and has zero interest in Jupiter any kind of romantic sense. Much to Jupiter’s dismay.
Eliza isn’t really interested in being a “god” but she understands the optics of the group looking united so she adopts the moniker of Juno and all the gifts and curses that come with it.